Like I said, same universe, but not a directly related, sequential film. Ridley Scott himself has said so, and he determines the canon. So his word, goes.
As a fun note, David follows the alphabetical line of robot names from the Alien films.
The robot in Alien was named Ash, the one in Aliens was Bishop, the one in Resurrection was named Cal. So A, B, C, and now D, David.